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1.
2.
Two main roles are identified in the review: the productive one, where woody perennials yield a material output (fuel, fodder, etc.), and the ‘service’ type, with no tangible product (shelter, nutrient recycling, etc.). In their productive role trees and shrubs may supply fodder in browsing systems, or industrial material, wood products and food in forest and plantation grazing systems. Service roles, rarely divorced from productive ones, arise mainly from relationships between woody perennials and the herbaceous vegetation growing in their vicinity. As a fodder source, the relatively low productivity and palatability of high protein content foliage from most woody perennials would indicate a supplementary role, particulary during dry seasons in arid and semiarid zones. In these type of lands pod-bearing trees seem to have a greater potential for improving fodder production in silvopastoral systems. The negative effect of trees on pasture production in forest and plantation grazing is compensated by their contribution to the system through other products. Available data would support the potential of certain species of woody perennials to foster pasture growing underneath, mainly through soil enrichment. Windbreaks can also indirectly benefit pasture growth, by decreasing water loss from the soil. It is postulated that research efforts in animal agroforestry should be focused on woody perennials for browsing systems, particularly on pod-bearing trees having beneficial effects on the herbaceous layer growing underneath.  相似文献   

3.
In the água de Gato Watershed on the island of Santiago, Cape Verde Islands, 51 farmers were surveyed regarding their attitudes and knowledge of agroforestry. The farmers identified eight constraints to agroforestry implementation, with virtually all indicating that a source of loan funds was the major concern. Space or land constraints and availability of tree seedlings were identified as constraints by 94% and 88%, respectively. Despite these concerns, 92% of the farmers expressed a willingness to adopt or improve agroforestry practices in the watershed, with 73% expressing a willingness to establish fruit trees, 53% willing to establish trees or shrubs for fuelwood, and 16% willing to plant trees for shade.  相似文献   

4.
The BAIF Development Research Foundation initiated an agroforestry extension project in Pune District, India in 1984, following earlier on-station research on leuceana-based alley-cropping systems for fodder. In extension meetings, farmers expressed a strong preference for planting a wide range of multipurpose trees on farm bunds and borders rather than single-species alley-cropping. Researcher-managed trials of proposed multipurpose species grown with crops were initiated, but were of limited value. An alternative approach to research was begun in 1988. This approach included a survey of agroforestry practices established by farmers through extension, and collection of data on crop yields by distance from the tree line from a sample of these plots. Research methods are described and modifications suggested for improving the quality of this type of extension-based research.  相似文献   

5.
The Turkana silvo-pastoral system is a traditional natural resource management strategy for dry lands that forms a sensible basis for improvement. Involvement of the local people is vital in adapting and improving the system, to bring out the potentials that exist in terms of broad land management strategies and more specifically in terms of individual tree species. The participatory extension process being used by the forestry department is presented. It relates to the traditional natural management base as a means of trying to identify potentials, constraints, problems and solutions. Such extension programmes are difficult to evaluate. The data gathering methods for evaluating such extension work, involving over 6000 people, is discussed in the light of a mobile people, lack of sampling frame and large distances in an arid and semi-arid environment. The results of two surveys, together with other informal data gathering mechanisms, show that change is taking place, particularly in qualitative terms, and indicates the effectiveness of the participatory extension programme.  相似文献   

6.
Science in agroforestry   总被引:20,自引:10,他引:20  
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7.
A study was conducted in Madhupur sal forest of Tangail, Bangladesh to identify the suitable agroforestry practices of the area. Considering the ecological aspects of different agroforestry practices 10 sample plots (10 m × 10 m) from each land uses were taken, including natural forest to get a comparative scenario. The study showed that among the different agroforestry practices, Margalef and Shannon-Weiner index values are the maximum for pineapple agroforestry and lower for banana agroforestry, and Evenness index value is the maximum for lemon agroforestry. Determination of tree biomass in different land uses revealed that it is highest (3 078.6 kg/100 m2) in natural forest followed by pineapple agroforestry, lemon agroforestry and banana agroforestry. Soil pH, moisture content, organic matter, organic carbon, phosphorus and total nitrogen showed statistically significant variation while bulk density, particle density, sulphur and potassium did not show any statistically significant variation among the land uses. Soil fertility status showed that pineapple agroforestry is more fertile than rest of other land uses. The Net Present Value (NPV) indicated that banana agroforestry is financially more profitable than other two systems, while the Benefit-Cost ratio (BCR) is higher in pineapple agroforestry (4.21 in participatory agroforestry and 3.35 in privately managed land). Even though banana agroforestry gives higher NPV, capital required for this practice is much higher. The findings suggest that pineapple agroforestry has a tendency towards becoming ecologically and economically more sound than other two practices as it has better ecological attributes and required comparatively low investment.  相似文献   

8.
The development of poplar agroforestry and associated research in India is reviewed. The model of agroforestry development involving a partnership between farmers, the private sector and the government is worthy of further investigation for application in other areas of India and to other countries. A number of suggestions are given for further research in the context of optimising the system for resource-poor farmers. These include changes in tree and crop varieties, tree spacing, and utilisation of small diameter logs, and other poplar products.  相似文献   

9.
This review encompasses results of fertilization experiments on several agroforestry systems—alley cropping, perennial shade systems, home gardens—in which fertilizer use is a likely management alternative. Fertilizer response was found to be most common in alley cropping, variable in perennial shade systems, and rarely reported in home gardens. Level of nutrient removal in harvested products is probably the overriding factor in determining fertilizer response; greater accumulation of organic residues, slower growth under shade, and longer periods of nutrient uptake probably also contribute to the relatively smaller fertilizer response of the perennial shade systems and home gardens. Considerable knowledge gaps exist regarding the breakdown of organic residues, and interactions between mineral and organic amendments. Systems based on annual crops (e.g., alley cropping) are likely to be less nutrient-efficient and sustainable than systems based on perennial crops, due to reduced fixation and transfer of N to the crops, the tendency of the trees to compete for and sequester nutrients, relatively high P requirements of the crops, and the high labor cost of tree management. The possible benefits of fertilization of specific components in home gardens, and relative advantages of including low-value tree legumes, high-value shade trees, and fertilization in shaded perennial systems are only beginning to receive research attention.  相似文献   

10.
The Homestead agroforestry system is very important in the economy of Bangladesh. The many woody species grown in the homesteads are a significant source of fuelwood; they also provide fodder, building materials and other forms of wood. In the context of the prevailing shortage of fuelwood and excessive deforestation in Bangladesh, this homestead agroforestry system needs to be strengthened. A field survey was undertaken to assess the prospects and feasibility of initiating a programme for the improvement of homestead agroforestry systems. It showed that the prospects for improving homestead agroforestry systems are good because most respondents own their homesteads and believe there is room for more trees on them. Although they know that raising trees is relatively difficult and requires special practices, they are familiar with the government nurseries and local agricultural extension officers, and are confident about the success of the programme. Results also indicate that multipurpose trees and specific modules for involving women in the farm operations are likely to enhance success of the programme.  相似文献   

11.
Although from the start ICRAF recognized the importance of the socio-economic dimensions of agroforestry land-use systems, it was only five years after its official commencement that an economist was added to the staff. During the last five years no attempt has been made to create a separate Economics Department with its own programme. Rather, the emphasis has been on supporting on-going ICRAF activities by trying to make “economics’ an integral part of eachof these activities.
    Nevertheless, in summarizing these efforts, five major areas of work can be identified:
  1. Economic concepts;
  2. Methods and tools for economic assessment;
  3. Economic information gathering;
  4. Economic analysis proper;
  5. Training and dissemination.
The achievements in each of these areas, as well as some ideas on possible trends, will be summarized in this paper.  相似文献   

12.
Many so-called society-oriented agroforestry programs, mainly in developing countries, fail because they do not take account of the social structure in their design. This study provides empirical evidence of the impact of social structure on the extent of on-farm tree growing. The study has been carried out in Mandi district of Himachal Pradesh, in Indian Western Himalaya. Analysis of survey data reveals significant relationships between extent of on-farm tree growing and caste, education of the head of household, family literacy, primary occupation, government employment, mobility of the household head, importance of tree growing for future generations, and holy tree worship practices. Households with concrete houses had more trees than households with mixed, mud and wooden houses. The study implies a need to consider social factors to encourage the level of on-farm tree growing and to design socially acceptable agroforestry programs. The study also emphasises the need for a holistic approach to agroforestry development by integrating other continuing rural development programs with that of agroforestry to increase the level of on-farm tree growing.  相似文献   

13.
The main agroforestry systems in Venezuela are the multispecies plant associations in integrated coffee production system and the silvopastoral system. This paper describes the functional and structural aspects of these systems. The multilayered coffee production systems are practised mainly in the premontane moist forest of the Andes region, but are also found in other areas of the country. Various tree species are used for shade and as fence in big coffee plantations, whereas in small units with traditional production pattern, coffee is planted along with many other species, often constituting a 3–4 layer canopy. Available data are presented on the production as well as some socioeconomic aspects.The silvopastoral systems are found in the tropical dry forest (savannas) and in the very dry tropical forest of the semiarid zones of the country. A large number of trees and shrubs are found in these pastoral areas where they play both productive (fodder and feed) and service (shelter) roles.Although both these systems are practised over large areas of the country, practically no research has been done to improve them. In order to strengthen national capability to undertake such research, international support of cash and as well as technical advice is needed.
Resumen Los principales sistemas agroforestales en Venezuela son el Sistema integrado de producción de café y el sistema silvopastoril. En el presente trabajo se describen aspectos funcionales y estructurales de esos sistemas. El sistema de producción multi-estratificado de café es practicado principalmente en el bosque húmedo premontano de la región andina, per también es frecuentemente observado en áreas del país. Diferentes especies de árboles son utilizados como sombra y como cercos vivos en las grandes plantaciones de café, mientras que en las pequenas unidades con un patrón de producción tradicional, el café es plantado junto con una gran diversidad de especies constituyendo un dosel vegetativo de 3–4 estratos.Información disponible sobre producción y algunos aspectos socio-económicos es presentada en el trabajo.Los sistemas silvopastoriles son encontrados en el bosque seco tropical (sabanas o llanos) y en el bosque muy seco tropical de las zonas semiaridas del país. Un gran número de árboles y arbustos se encuentran en esas áreas de pastoreo donde juegan un doble rol, producción (forraje ya alimento) y servicio (refugio y abrigo).Aunque ambos sistemas son practicados en grandes áreas del país, practicamente ninguna investigación se ha llevado a cabo para mejoralos. Con el objeto de fortalecer la capacidad en el país de llevar a cabo tal tipo de investigación, se hace necessario recursos economicós y asesaría técnica por parte de organizaciones internacionales.
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14.
Jose  S.  Gillespie  A.R.  Pallardy  S.G. 《Agroforestry Systems》2004,61(1-3):237-255
Agroforestry Systems - The ecological principles that define the competitive and complementary interactions among trees, crops, and fauna in agroforestry systems have received considerable research...  相似文献   

15.
Economic benefits that can accrue to the small farmer from incorporating trees in his farm system, and the economic constraints and costs he may face in doing so, are reviewed. Various economic considerations other than cash outlays and incomings, such as impact of risk, need to be taken into account. Issues are discussed that can arise in identifying, designing and implementing projects intended to help farmers to capture the economic potentials of agroforestry and to avoid or remove related economic impediments. Correct understanding of the factors which will affect the success of project interventions, valuation of the costs and benefits of trees as perceived by the farmer rather than by outsiders, distributional and equity issues, and identification of operational measures to ensure tangible short-term economic benefits are highlighted. The need for giving priority to research into the economic impacts of agroforestry practices on small farmer situations is stressed.  相似文献   

16.
Simons  A.J.  Leakey  R.R.B. 《Agroforestry Systems》2004,61(1-3):167-181
Agroforestry Systems - We execute tree ‘domestication’ as a farmer-driven and market-led process, which matches the intraspecific diversity of locally important trees to the needs of...  相似文献   

17.
Traditional agroforestry systems in the communal areas of Zimbabwe are described. There are systems centered on main fields, on home gardens, on homesites and on grazing areas. In the main fields, the major tree-related management practice is the conservation of preferred indigenous fruit trees. Fruit trees are also the focus of forestry activities around the gardens and the homesite; but here it is the planting of exotic species. In a localized area of Zimbabwe Acacia albida is important in fields. There is almost no use of tree fallows in Zimbabwe. Trees in grazing areas have numerous roles, but at present there is little knowledge about traditional management practices in these areas. In the development of agroforestry systems in Zimbabwe it is suggested that those systems designed to improve fodder production will make a significant contribution to farm productivity because of the importance of cattle in the farming system and the present fodder shortage. Interventions involving the planting of fruit trees are likely to be very successful, as there is much interest in such planting. Another area that needs to be developed is that of tree plantings to improve soil fertility.  相似文献   

18.
Historical development of agroforestry in China   总被引:3,自引:0,他引:3  
In China both agriculture and agroforestry originated in forests and developed side by side from their very beginnings. As revealed by archaeological evidence from ancient times, ancestral Chinese inhabited forests where they sheltered themselves from external hazards and lived on the edible parts of plants and animals through hunting and gathering activities.As early as the New Stone Age (7000–8000 years B.C.), fire was commonly used to burn the forests for slash-and-burn cultivation, which is a primitive form of agroforestry. Along with the rapid growth of population, the annexing of tribes, the collapse of clan society and the development of the slavery system, the nomadic mode of slash-and-burn farming evolved into settlement farming in the Xia Dynasty (2000-1600 B.C.). Peasants then engaged in settled cultivation.During the Shang and West Zhou Dynasty (1600-800 B.C.), perpetual settlement farming encouraged the development of private land-ownership. Peasants planted trees in or around the crop fields and grew fruit plants, vegetables and farmed domestic animals in their home yards for self-sufficiency. Since then, various forms of agroforestry have gradually developed and laid the fundamental framework of the Chinese small-farming economy for more than 3000 years.There has been a rapid growth of population in China over since the 1950s. At the same time, the area of arable land has decreased drastically and the environment has degraded rapidly as industrial development has taken place. The traditional labour-consuming and ineffective agroforestry management practices have not adapted to the current situation. In view of economic, ecological and social benefits, conversion of mono-biological production into a trinity system of agriculture, processing and marketing is suggested and planned experimentally. Such a management system, known as modern agroforestry, could be very beneficial to the development of modern China's rural economy and environmental conservation.  相似文献   

19.
India is perhaps the world leader in development of agroforestry education, training and research. The Indian Council of Agricultural Research sanctioned an All-India Coordinated Research Project on agroforestry in 1983, to be headquartered in Delhi but with research centers in 20 other locations countrywide. The agricultural universities in India have a major role to play, with all institutions having agroforestry teaching programs by 1990. At this point there is a great shortage of faculty trained in agroforestry. Demand for qualified graduates with this training is only going to increase.  相似文献   

20.
Plant species and cultivars of the indigenous agroforestry system of Pohnpei were surveyed in transects through 54 randomly-selected farms. The agroforestry system was characterized by extensive cultivation of yams (Dioscorea), aroids (Alocasia), and Piper methysticum under a permanent overstory of breadfruit, coconut, and forest remnant trees and a middle canopy of Hibiscus tiliaceus, Musa spp., and Morinda citrifolia. In the 10 ha of survey plots, 161 species were found, of which 102 were trees, shrubs, and crops and 59 were uncultivated herbaceous plants. Numbers of tree, shrub, and crop species per farm ranged from 16 to 37 with an average of 26. Twenty-eight breadfruit and 38 yam cultivars were found in the survey plots, showing that cultivar diversity is an important component of the biological diversity maintained and utilized in Pohnpeian agroforests.  相似文献   

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